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2012.01.16Ultra-Precision Cutting Tool “UPC®” New Series Placed on the Market – “BL-UPC” Employing “SumiDIA Binderless” for the Cutting Edge –

Introducing the Newly Developed Product

Mirror finishing and nano-/micro-cutting of cemented carbide and high-hardness materials have now become possible with the ultra-precision cutting tool “UPC®” Series.

A.L.M.T. Corp. has developed and will soon start marketing the new series “BL-UPC” that employs “SumiDIA Binderless” （∗1）, nano-polycrystalline diamond, for the cutting edge of the ultra-precision diamond cutting tool “UPC.” This Series enables ulltra-precision machining of high-hardness materials such as cemented carbide that have been impossible to cut with conventional tools and meets ever increasing needs of finer and higher accuracy machining.

1．Overview
The ultra-precision diamond cutting tool “UPC” Series employs commonly used synthetic single crystal diamond for the cutting edge and has been widely used in machining molds of various plastic lenses. Since these molds are made of soft metals such as electroless nickel, they can be machined with the conventional “UPC” to nanometer accuracy.
In contrast, the molds of high performance glass lenses that are superior in optical and heat-resistant properties used in such equipment as digital cameras and sensors are made of high-hardness materials such as cemented carbide. When cutting these materials, the cutting edge of the conventional “UPC” is easily chipped, and general-purpose tools that use sintered diamond are not sharp enough and have such problems as consistency of accuracy and tool life. Thus, these molds are very difficult to fabricate by cutting and a predominant method employed at present is grinding by use of diamond grinding wheels, etc.
The newly developed “BL-UPC” Series fully exploits the characteristics of “SumiDIA Binderless,” nano-polycrystallilne diamond. This is a cutting tool equipped with both a sharp cutting edge，a feature of single crystal diamond, and high chipping resistance, a feature of polycrystalline diamond. With these features, this Series enables ultra-precision machining such as mirror finishing of cemented carbide and other high-hardness materials by cutting. We will start studying ultra-precision machining of such materials as glass and SiC also.

2．Features （Comparison with grinding）
To machine small concave molds by grinding, the diameter of diamond grinding wheels needs to be small and accordingly the number of acting diamond abrasives becomes small. Also truing (∗2) required to achieve submicron form accuracy and nanometer-level surface roughness is very difficult. These problems have made it difficult to create ultra-precise molds having a consistent form with little variation by grinding and limited grinding wheels to a certain diameter.
In contrast, cutting by use of the newly developed “BL-UPC” Series requires no truing during machining. Furthermore, the movement of ultra-precision machines can precisely be transferred to molds, making it possible to obtain both submicron form accuracy and nanometer-level surface roughness easily. Also in machining concave surfaces less than Φ 0.1 mm, the “BL-UPC” can be combined with an elliptical vibration machine to achieve a deeper depth of cut and faster feed rate, thus making this Series applicable to mass production of molds of cemented carbide and other high-hardness materials like ordinary mold machining with the proven conventional “UPC.”

3．Outlook
As the performance of products has been improved, glass optical devices have become much smaller and more functional. Consequently, needs for products that are difficult to process such as incorporating micro patterns like diffraction grating as well as simple lens faces have been increasing. Such products cannot be made successfully only with tools having a simple shape, but require endmill type cutting tools capable of complex three dimensional machining. There are also needs to directly cut glass lenses, as well as molds of glass lenses. A.L.M.T. Corp. intends to develop and market “Nano Ballendmill” and “Nano Profile” that, as with the conventional “UPC,” employ “SumiDIA Binderless” in order to meet various machining needs. As a range of selection is expanded to include the “BL-UPC,” it is expected that our cutting tools will be used in wider applications including machining molds of medical examination glass components such as micro reactors and ultra-precision machining of micromachine components, in addition to machining molds of glass optical devices.

4．“BL-UPC” Series to be Placed on the Market

（1）

UPC-R Round edge

Aspherical surface machining tool

（2）

UPC-T Triangular edge

Fine grooving tool

（3）

Nano Ballendmill

Fine 3-D machining ball endmill

5．Applications

（1）

Machining glass lens molds and glass lenses

（2）

Maching micro lens arrays and their molds (for optical communications and various sensors)

Polycrystalline diamond developed by Sumitomo Electric Industries, Ltd., an affiliate company. This product uses no binder and is almost 100% diamond, yet not anisotropic and has homogeneous performance.
“SumiDIA” is a registered trademark of Sumitomo Electric Industries, Ltd.

(∗2) Truing

An operation to shave the surface of grinding wheels that wears and deforms as they are used with such equipment as a diamond dresser in order to correct the concentricity and shape.

A.L.M.T. Corp. has met needs of society over half a century with tungsten and molybdenum that are materials having a ultra-high melting point, and heatspreader materials using these materials, electronic parts and functional parts and with precision tools made of diamond and cBN.
We make full use of our technological strength and abundant know-how to bring about further added values to an ever-evolving highly sensitive society.